Shanahan unsure if McNabb will be ready for Dallas game

ASHBURN, Va. -- It could be a smoke screen or just a cautious assessment of his quarterback's health, but Mike Shanahan says he's not certain that Donovan McNabb will be available for the Washington Redskins' season opener against the Dallas Cowboys.

"I really don't know for sure," Shanahan said Sunday. "That's why it's day by day. We'll see how it goes."

McNabb hasn't practiced since spraining his left ankle in the second preseason game against Baltimore. He sat out Friday's game against the New York Jets and watched Sunday's practice with a black sleeve on his left leg.

Shanahan said the leg is too sore for McNabb to play this week against the Arizona Cardinals, but McNabb likely wouldn't have played in that game anyway because the coach prefers to rest his starter in the final exhibition to avoid injury.

However, backup quarterback Rex Grossman said he won't play this week either, perhaps as an insurance policy to make sure at least one of the top two quarterbacks on the roster is ready to go against the Cowboys on Sept. 12.

That leaves bubble quarterbacks John Beck and Richard Bartel taking the snaps Thursday at Arizona.

The news from Shanahan was more positive concerning running back Clinton Portis, who sprained his right ankle against the Jets.

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"I don't think it's too serious. It's not a big setback," Shanahan said. "I would anticipate him being able to practice in a couple of days."

Fullback Mike Sellers, who missed the Jets game, remains day to day with a sprained left knee. Backup linebacker Perry Riley sprained his right ankle against New York and was wearing a walking boot Sunday.